Checking the vacuum in the intake manifold (Mitsubishi Lancer 9)

1. Before starting the inspection procedure, prepare the vehicle (see section "Checking the idle speed").

2. Turn off the ignition, then connect the tester to the diagnostic connector or connect the tachometer to the service connector.

3. Disconnect the hose from the positive crankcase ventilation valve and connect a vacuum gauge to the hose. Close the valve opening with a plug.











4. Start the engine and let it idle.

Note: (GDI engine) After starting, the engine must be allowed to idle for at least four minutes.

5. Check the intake manifold vacuum with the engine idling at base speed.

Nominal value:

• 4G15-GDI — not less than 27.6 kPa
• 4G93-GDI — not less than 60 kPa
• 4G15-MPI - not less than 61.2 kPa
• 4G93-MPI - not less than 60 kPa

Note: If the measured vacuum in the intake manifold does not correspond to the nominal value, then check for faults in the intake system (air leaks), as well as the condition of the vacuum lines of other systems connected to the intake manifold.

6. Stop the engine and turn the ignition key to the "LOCK" (OFF) position.

7. Disconnect the vacuum gauge from the vacuum hose, then connect the vacuum hose to the positive crankcase ventilation valve.

8. Disconnect the tester or tachometer.